As Mississippi Power Co. draws closer to collecting for the $3 billion-plus Kemper County plant it's building, a company customer wants the Mississippi Supreme Court to rule utilities can't raise rates for power plants before they start making electricity.

Thomas Blanton, a Mississippi Power customer from Hattiesburg, says 2008's Baseload Act is an unconstitutional tax.

Blanton got his day in court after intervening in a case Mississippi Power filed against the Public Service Commission. The regulatory body denied the company's request to begin collecting money for the plant.

The PSC and Mississippi Power settled Thursday, with the commission agreeing to consider a new request for during-construction rates. Mississippi Power asked for a 21 percent rate increase Friday.